Wireless uplink resource allocation

ABSTRACT

A wireless device may receive configuration parameters of cells comprising a primary cell that is not configured with scheduling request (SR) resources and a secondary cell that is configured with SR resources and that is in a secondary timing advance group (sTAG). A wireless device may determine to perform an SR process. Based on the wireless device not having an uplink data channel resource available in a time interval and not having a valid timing advance for the secondary cell in the time interval, the wireless device may initiate a random access procedure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/522,397, filed Jul. 25, 2019, which is a continuation of U.S. patentapplication Ser. No. 15/951,499, filed Apr. 12, 2018, now U.S. Pat. No.10,454,734, which is a continuation of U.S. patent application Ser. No.15/162,779, filed May 24, 2016, now U.S. Pat. No. 9,948,487, whichclaims the benefit of U.S. Provisional Application No. 62/175,867, filedJun. 15, 2015, each of the above of which is hereby incorporated byreference in its entirety.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Examples of several of the various embodiments of the present inventionare described herein with reference to the drawings.

FIG. 1 is a diagram depicting example sets of OFDM subcarriers as per anaspect of an embodiment of the present invention.

FIG. 2 is a diagram depicting an example transmission time and receptiontime for two carriers in a carrier group as per an aspect of anembodiment of the present invention.

FIG. 3 is a diagram depicting OFDM radio resources as per an aspect ofan embodiment of the present invention.

FIG. 4 is a block diagram of a base station and a wireless device as peran aspect of an embodiment of the present invention.

FIG. 5A, FIG. 5B, FIG. 5C and FIG. 5D are example diagrams for uplinkand downlink signal transmission as per an aspect of an embodiment ofthe present invention.

FIG. 6 is an example diagram for a protocol structure with CA and DC asper an aspect of an embodiment of the present invention.

FIG. 7 is an example diagram for a protocol structure with CA and DC asper an aspect of an embodiment of the present invention.

FIG. 8 shows example TAG configurations as per an aspect of anembodiment of the present invention.

FIG. 9 is an example message flow in a random access process in asecondary TAG as per an aspect of an embodiment of the presentinvention.

FIG. 10 is an example grouping of cells into PUCCH groups as per anaspect of an embodiment of the present invention.

FIG. 11 illustrates example groupings of cells into one or more PUCCHgroups and one or more TAGs as per an aspect of an embodiment of thepresent invention.

FIG. 12 illustrates example groupings of cells into one or more PUCCHgroups and one or more TAGs as per an aspect of an embodiment of thepresent invention.

FIG. 13 is an example MAC PDU as per an aspect of an embodiment of thepresent invention.

FIG. 14 is an example SR periodicity and subframe offset configurationas per an aspect of an embodiment of the present invention.

FIG. 15 is an example SR process as per an aspect of an embodiment ofthe present invention.

FIG. 16 shows example events and states corresponding to a secondarycell as per an aspect of an embodiment of the present invention.

FIG. 17 shows example events and states corresponding to a secondarycell as per an aspect of an embodiment of the present invention.

FIG. 18 shows example events and states corresponding to a secondarycell as per an aspect of an embodiment of the present invention.

FIG. 19 shows example events and states corresponding to a secondarycell as per an aspect of an embodiment of the present invention.

FIG. 20 shows example events and states corresponding to a secondarycell as per an aspect of an embodiment of the present invention.

FIG. 21 is an example flow diagram as per an aspect of an embodiment ofthe present invention.

FIG. 22 is an example flow diagram as per an aspect of an embodiment ofthe present invention.

FIG. 23 is an example flow diagram as per an aspect of an embodiment ofthe present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

Example embodiments of the present invention enable operation ofmultiple physical uplink control channel (PUCCH) groups. Embodiments ofthe technology disclosed herein may be employed in the technical fieldof multicarrier communication systems. More particularly, theembodiments of the technology disclosed herein may relate to operationof PUCCH groups.

The following Acronyms are used throughout the present disclosure:

ASIC application-specific integrated circuit

BPSK binary phase shift keying

CA carrier aggregation

CSI channel state information

CDMA code division multiple access

CSS common search space

CPLD complex programmable logic devices

CC component carrier

DL downlink

DCI downlink control information

DC dual connectivity

EPC evolved packet core

E-UTRAN evolved-universal terrestrial radio access network

FPGA field programmable gate arrays

FDD frequency division multiplexing

HDL hardware description languages

HARQ hybrid automatic repeat request

IE information element

LTE long term evolution

MCG master cell group

MeNB master evolved node B

MIB master information block

MAC media access control

MAC media access control

MME mobility management entity

NAS non-access stratum

OFDM orthogonal frequency division multiplexing

PDCP packet data convergence protocol

PDU packet data unit

PHY physical

PDCCH physical downlink control channel

PHICH physical HARQ indicator channel

PUCCH physical uplink control channel

PUSCH physical uplink shared channel

PCell primary cell

PCell primary cell

PCC primary component carrier

PSCell primary secondary cell

pTAG primary timing advance group

QAM quadrature amplitude modulation

QPSK quadrature phase shift keying

RBG Resource Block Groups

RLC radio link control

RRC radio resource control

RA random access

RB resource blocks

SCC secondary component carrier

SCell secondary cell

Scell secondary cells

SCG secondary cell group

SeNB secondary evolved node B

sTAGs secondary timing advance group

SDU service data unit

S-GW serving gateway

SRB signaling radio bearer

SC-OFDM single carrier-OFDM

SFN system frame number

SIB system information block

TAI tracking area identifier

TAT time alignment timer

TDD time division duplexing

TDMA time division multiple access

TA timing advance

TAG timing advance group

TB transport block

UL uplink

UE user equipment

VHDL VHSIC hardware description language

Example embodiments of the invention may be implemented using variousphysical layer modulation and transmission mechanisms. Exampletransmission mechanisms may include, but are not limited to: CDMA, OFDM,TDMA, Wavelet technologies, and/or the like. Hybrid transmissionmechanisms such as TDMA/CDMA, and OFDM/CDMA may also be employed.Various modulation schemes may be applied for signal transmission in thephysical layer. Examples of modulation schemes include, but are notlimited to: phase, amplitude, code, a combination of these, and/or thelike. An example radio transmission method may implement QAM using BPSK,QPSK, 16-QAM, 64-QAM, 256-QAM, and/or the like. Physical radiotransmission may be enhanced by dynamically or semi-dynamically changingthe modulation and coding scheme depending on transmission requirementsand radio conditions.

FIG. 1 is a diagram depicting example sets of OFDM subcarriers as per anaspect of an embodiment of the present invention. As illustrated in thisexample, arrow(s) in the diagram may depict a subcarrier in amulticarrier OFDM system. The OFDM system may use technology such asOFDM technology, SC-OFDM technology, or the like. For example, arrow 101shows a subcarrier transmitting information symbols. FIG. 1 is forillustration purposes, and a typical multicarrier OFDM system mayinclude more subcarriers in a carrier. For example, the number ofsubcarriers in a carrier may be in the range of 10 to 10,000subcarriers. FIG. 1 shows two guard bands 106 and 107 in a transmissionband. As illustrated in FIG. 1 , guard band 106 is between subcarriers103 and subcarriers 104. The example set of subcarriers A 102 includessubcarriers 103 and subcarriers 104. FIG. 1 also illustrates an exampleset of subcarriers B 105. As illustrated, there is no guard band betweenany two subcarriers in the example set of subcarriers B 105. Carriers ina multicarrier OFDM communication system may be contiguous carriers,non-contiguous carriers, or a combination of both contiguous andnon-contiguous carriers.

FIG. 2 is a diagram depicting an example transmission time and receptiontime for two carriers as per an aspect of an embodiment of the presentinvention. A multicarrier OFDM communication system may include one ormore carriers, for example, ranging from 1 to 10 carriers. Carrier A 204and carrier B 205 may have the same or different timing structures.Although FIG. 2 shows two synchronized carriers, carrier A 204 andcarrier B 205 may or may not be synchronized with each other. Differentradio frame structures may be supported for FDD and TDD duplexmechanisms. FIG. 2 shows an example FDD frame timing. Downlink anduplink transmissions may be organized into radio frames 201. In thisexample, radio frame duration is 10 msec. Other frame durations, forexample, in the range of 1 to 100 msec may also be supported. In thisexample, each 10 msec radio frame 201 may be divided into ten equallysized subframes 202. Other subframe durations such as including 0.5msec, 1 msec, 2 msec, and 5 msec may also be supported. Subframe(s) mayconsist of two or more slots (e.g. slots 206 and 207). For the exampleof FDD, 10 subframes may be available for downlink transmission and 10subframes may be available for uplink transmissions in each 10 msecinterval. Uplink and downlink transmissions may be separated in thefrequency domain. Slot(s) may include a plurality of OFDM symbols 203.The number of OFDM symbols 203 in a slot 206 may depend on the cyclicprefix length and subcarrier spacing.

FIG. 3 is a diagram depicting OFDM radio resources as per an aspect ofan embodiment of the present invention. The resource grid structure intime 304 and frequency 305 is illustrated in FIG. 3 . The quantity ofdownlink subcarriers or RBs (in this example 6 to 100 RBs) may depend,at least in part, on the downlink transmission bandwidth 306 configuredin the cell. The smallest radio resource unit may be called a resourceelement (e.g. 301). Resource elements may be grouped into resourceblocks (e.g. 302). Resource blocks may be grouped into larger radioresources called Resource Block Groups (RBG) (e.g. 303). The transmittedsignal in slot 206 may be described by one or several resource grids ofa plurality of subcarriers and a plurality of OFDM symbols. Resourceblocks may be used to describe the mapping of certain physical channelsto resource elements. Other pre-defined groupings of physical resourceelements may be implemented in the system depending on the radiotechnology. For example, 24 subcarriers may be grouped as a radio blockfor a duration of 5 msec. In an illustrative example, a resource blockmay correspond to one slot in the time domain and 180 kHz in thefrequency domain (for 15 KHz subcarrier bandwidth and 12 subcarriers).

FIG. 5A, FIG. 5B, FIG. 5C and FIG. 5D are example diagrams for uplinkand downlink signal transmission as per an aspect of an embodiment ofthe present invention. FIG. 5A shows an example uplink physical channel.The baseband signal representing the physical uplink shared channel mayperform the following processes. These functions are illustrated asexamples and it is anticipated that other mechanisms may be implementedin various embodiments. The functions may comprise scrambling,modulation of scrambled bits to generate complex-valued symbols, mappingof the complex-valued modulation symbols onto one or severaltransmission layers, transform precoding to generate complex-valuedsymbols, precoding of the complex-valued symbols, mapping of precodedcomplex-valued symbols to resource elements, generation ofcomplex-valued time-domain SC-FDMA signal for each antenna port, and/orthe like.

Example modulation and up-conversion to the carrier frequency of thecomplex-valued SC-FDMA baseband signal for each antenna port and/or thecomplex-valued PRACH baseband signal is shown in FIG. 5B. Filtering maybe employed prior to transmission.

An example structure for Downlink Transmissions is shown in FIG. 5C. Thebaseband signal representing a downlink physical channel may perform thefollowing processes. These functions are illustrated as examples and itis anticipated that other mechanisms may be implemented in variousembodiments. The functions include scrambling of coded bits in each ofthe codewords to be transmitted on a physical channel; modulation ofscrambled bits to generate complex-valued modulation symbols; mapping ofthe complex-valued modulation symbols onto one or several transmissionlayers; precoding of the complex-valued modulation symbols on each layerfor transmission on the antenna ports; mapping of complex-valuedmodulation symbols for each antenna port to resource elements;generation of complex-valued time-domain OFDM signal for each antennaport, and/or the like.

Example modulation and up-conversion to the carrier frequency of thecomplex-valued OFDM baseband signal for each antenna port is shown inFIG. 5D. Filtering may be employed prior to transmission.

FIG. 4 is an example block diagram of a base station 401 and a wirelessdevice 406, as per an aspect of an embodiment of the present invention.A communication network 400 may include at least one base station 401and at least one wireless device 406. The base station 401 may includeat least one communication interface 402, at least one processor 403,and at least one set of program code instructions 405 stored innon-transitory memory 404 and executable by the at least one processor403. The wireless device 406 may include at least one communicationinterface 407, at least one processor 408, and at least one set ofprogram code instructions 410 stored in non-transitory memory 409 andexecutable by the at least one processor 408. Communication interface402 in base station 401 may be configured to engage in communicationwith communication interface 407 in wireless device 406 via acommunication path that includes at least one wireless link 411.Wireless link 411 may be a bi-directional link. Communication interface407 in wireless device 406 may also be configured to engage in acommunication with communication interface 402 in base station 401. Basestation 401 and wireless device 406 may be configured to send andreceive data over wireless link 411 using multiple frequency carriers.According to some of the various aspects of embodiments, transceiver(s)may be employed. A transceiver is a device that includes both atransmitter and receiver. Transceivers may be employed in devices suchas wireless devices, base stations, relay nodes, and/or the like.Example embodiments for radio technology implemented in communicationinterface 402, 407 and wireless link 411 are illustrated are FIG. 1 ,FIG. 2 , FIG. 3 , FIG. 5 , and associated text.

An interface may be a hardware interface, a firmware interface, asoftware interface, and/or a combination thereof. The hardware interfacemay include connectors, wires, electronic devices such as drivers,amplifiers, and/or the like. A software interface may include codestored in a memory device to implement protocol(s), protocol layers,communication drivers, device drivers, combinations thereof, and/or thelike. A firmware interface may include a combination of embeddedhardware and code stored in and/or in communication with a memory deviceto implement connections, electronic device operations, protocol(s),protocol layers, communication drivers, device drivers, hardwareoperations, combinations thereof, and/or the like.

The term configured may relate to the capacity of a device whether thedevice is in an operational or non-operational state. Configured mayalso refer to specific settings in a device that effect the operationalcharacteristics of the device whether the device is in an operational ornon-operational state. In other words, the hardware, software, firmware,registers, memory values, and/or the like may be “configured” within adevice, whether the device is in an operational or nonoperational state,to provide the device with specific characteristics. Terms such as “acontrol message to cause in a device” may mean that a control messagehas parameters that may be used to configure specific characteristics inthe device, whether the device is in an operational or non-operationalstate.

According to some of the various aspects of embodiments, an LTE networkmay include a multitude of base stations, providing a user planePDCP/RLC/MAC/PHY and control plane (RRC) protocol terminations towardsthe wireless device. The base station(s) may be interconnected withother base station(s) (e.g. employing an X2 interface). The basestations may also be connected employing, for example, an S1 interfaceto an EPC. For example, the base stations may be interconnected to theMME employing the S1-MME interface and to the S-G) employing the S1-Uinterface. The S1 interface may support a many-to-many relation betweenMMEs/Serving Gateways and base stations. A base station may include manysectors for example: 1, 2, 3, 4, or 6 sectors. A base station mayinclude many cells, for example, ranging from 1 to 50 cells or more. Acell may be categorized, for example, as a primary cell or secondarycell. At RRC connection establishment/re-establishment/handover, oneserving cell may provide the NAS (non-access stratum) mobilityinformation (e.g. TAI), and at RRC connection re-establishment/handover,one serving cell may provide the security input. This cell may bereferred to as the Primary Cell (PCell). In the downlink, the carriercorresponding to the PCell may be the Downlink Primary Component Carrier(DL PCC), while in the uplink, it may be the Uplink Primary ComponentCarrier (UL PCC). Depending on wireless device capabilities, SecondaryCells (SCells) may be configured to form together with the PCell a setof serving cells. In the downlink, the carrier corresponding to an SCellmay be a Downlink Secondary Component Carrier (DL SCC), while in theuplink, it may be an Uplink Secondary Component Carrier (UL SCC). AnSCell may or may not have an uplink carrier.

A cell, comprising a downlink carrier and optionally an uplink carrier,may be assigned a physical cell ID and a cell index. A carrier (downlinkor uplink) may belong to only one cell. The cell ID or Cell index mayalso identify the downlink carrier or uplink carrier of the cell(depending on the context it is used). In the specification, cell ID maybe equally referred to a carrier ID, and cell index may be referred tocarrier index. In implementation, the physical cell ID or cell index maybe assigned to a cell. A cell ID may be determined using asynchronization signal transmitted on a downlink carrier. A cell indexmay be determined using RRC messages. For example, when thespecification refers to a first physical cell ID for a first downlinkcarrier, the specification may mean the first physical cell ID is for acell comprising the first downlink carrier. The same concept may applyto, for example, carrier activation. When the specification indicatesthat a first carrier is activated, the specification may equally meanthat the cell comprising the first carrier is activated.

Embodiments may be configured to operate as needed. The disclosedmechanism may be performed when certain criteria are met, for example,in a wireless device, a base station, a radio environment, a network, acombination of the above, and/or the like. Example criteria may bebased, at least in part, on for example, traffic load, initial systemset up, packet sizes, traffic characteristics, a combination of theabove, and/or the like. When the one or more criteria are met, variousexample embodiments may be applied. Therefore, it may be possible toimplement example embodiments that selectively implement disclosedprotocols.

A base station may communicate with a mix of wireless devices. Wirelessdevices may support multiple technologies, and/or multiple releases ofthe same technology. Wireless devices may have some specificcapability(ies) depending on its wireless device category and/orcapability(ies). A base station may comprise multiple sectors. When thisdisclosure refers to a base station communicating with a plurality ofwireless devices, this disclosure may refer to a subset of the totalwireless devices in a coverage area. This disclosure may refer to, forexample, a plurality of wireless devices of a given LTE release with agiven capability and in a given sector of the base station. Theplurality of wireless devices in this disclosure may refer to a selectedplurality of wireless devices, and/or a subset of total wireless devicesin a coverage area which perform according to disclosed methods, and/orthe like. There may be a plurality of wireless devices in a coveragearea that may not comply with the disclosed methods, for example,because those wireless devices perform based on older releases of LTEtechnology.

FIG. 6 and FIG. 7 are example diagrams for protocol structure with CAand DC as per an aspect of an embodiment of the present invention.E-UTRAN may support Dual Connectivity (DC) operation whereby a multipleRX/TX UE in RRC_CONNECTED may be configured to utilize radio resourcesprovided by two schedulers located in two eNBs connected via a non-idealbackhaul over the X2 interface. eNBs involved in DC for a certain UE mayassume two different roles: an eNB may either act as an MeNB or as anSeNB. In DC a UE may be connected to one MeNB and one SeNB. Mechanismsimplemented in DC may be extended to cover more than two eNBs. FIG. 7illustrates one example structure for the UE side MAC entities when aMaster Cell Group (MCG) and a Secondary Cell Group (SCG) are configured,and it may not restrict implementation. Media Broadcast MulticastService (MBMS) reception is not shown in this figure for simplicity.

In DC, the radio protocol architecture that a particular bearer uses maydepend on how the bearer is setup. Three alternatives may exist, an MCGbearer, an SCG bearer and a split bearer as shown in FIG. 6 . RRC may belocated in MeNB and SRBs may be configured as a MCG bearer type and mayuse the radio resources of the MeNB. DC may also be described as havingat least one bearer configured to use radio resources provided by theSeNB. DC may or may not be configured/implemented in example embodimentsof the invention.

In the case of DC, the UE may be configured with two MAC entities: oneMAC entity for MeNB, and one MAC entity for SeNB. In DC, the configuredset of serving cells for a UE may comprise of two subsets: the MasterCell Group (MCG) containing the serving cells of the MeNB, and theSecondary Cell Group (SCG) containing the serving cells of the SeNB. Fora SCG, one or more of the following may be applied: at least one cell inthe SCG has a configured UL CC and one of them, named PSCell (or PCellof SCG, or sometimes called PCell), is configured with PUCCH resources;when the SCG is configured, there may be at least one SCG bearer or oneSplit bearer; upon detection of a physical layer problem or a randomaccess problem on a PSCell, or the maximum number of RLC retransmissionshas been reached associated with the SCG, or upon detection of an accessproblem on a PSCell during a SCG addition or a SCG change: a RRCconnection re-establishment procedure may not be triggered, ULtransmissions towards cells of the SCG are stopped, a MeNB may beinformed by the UE of a SCG failure type, for split bearer, the DL datatransfer over the MeNB is maintained; the RLC AM bearer may beconfigured for the split bearer; like PCell, PSCell may not bede-activated; PSCell may be changed with a SCG change (e.g. withsecurity key change and a RACH procedure); and/or neither a directbearer type change between a Split bearer and a SCG bearer norsimultaneous configuration of a SCG and a Split bearer are supported.

With respect to the interaction between a MeNB and a SeNB, one or moreof the following principles may be applied: the MeNB may maintain theRRM measurement configuration of the UE and may, (e.g., based onreceived measurement reports or traffic conditions or bearer types),decide to ask a SeNB to provide additional resources (serving cells) fora UE; upon receiving a request from the MeNB, a SeNB may create acontainer that may result in the configuration of additional servingcells for the UE (or decide that it has no resource available to do so);for UE capability coordination, the MeNB may provide (part of) the ASconfiguration and the UE capabilities to the SeNB; the MeNB and the SeNBmay exchange information about a UE configuration by employing of RRCcontainers (inter-node messages) carried in X2 messages; the SeNB mayinitiate a reconfiguration of its existing serving cells (e.g., PUCCHtowards the SeNB); the SeNB may decide which cell is the PSCell withinthe SCG; the MeNB may not change the content of the RRC configurationprovided by the SeNB; in the case of a SCG addition and a SCG SCelladdition, the MeNB may provide the latest measurement results for theSCG cell(s); both a MeNB and a SeNB may know the SFN and subframe offsetof each other by OAM, (e.g., for the purpose of DRX alignment andidentification of a measurement gap). In an example, when adding a newSCG SCell, dedicated RRC signalling may be used for sending requiredsystem information of the cell as for CA, except for the SFN acquiredfrom a MIB of the PSCell of a SCG.

According to some of the various aspects of embodiments, serving cellshaving an uplink to which the same time alignment (TA) applies may begrouped in a TA group (TAG). Serving cells in one TAG may use the sametiming reference. For a given TAG, user equipment (UE) may use onedownlink carrier as a timing reference at a given time. The UE may use adownlink carrier in a TAG as a timing reference for that TAG. For agiven TAG, a UE may synchronize uplink subframe and frame transmissiontiming of uplink carriers belonging to the same TAG. According to someof the various aspects of embodiments, serving cells having an uplink towhich the same TA applies may correspond to serving cells hosted by thesame receiver. A TA group may comprise at least one serving cell with aconfigured uplink. A UE supporting multiple TAs may support two or moreTA groups. One TA group may contain the PCell and may be called aprimary TAG (pTAG). In a multiple TAG configuration, at least one TAgroup may not contain the PCell and may be called a secondary TAG(sTAG). Carriers within the same TA group may use the same TA value andthe same timing reference. When DC is configured, cells belonging to acell group (MCG or SCG) may be grouped into multiple TAGs including apTAG and one or more sTAGs.

FIG. 8 shows example TAG configurations as per an aspect of anembodiment of the present invention. In Example 1, pTAG comprises PCell,and an sTAG comprises SCell1. In Example 2, a pTAG comprises a PCell andSCell1, and an sTAG comprises SCell2 and SCell3. In Example 3, pTAGcomprises PCell and SCell1, and an sTAG1 includes SCell2 and SCell3, andsTAG2 comprises SCell4. Up to four TAGs may be supported in a cell group(MCG or SCG) and other example TAG configurations may also be provided.In various examples in this disclosure, example mechanisms are describedfor a pTAG and an sTAG. The operation with one example sTAG isdescribed, and the same operation may be applicable to other sTAGs. Theexample mechanisms may be applied to configurations with multiple sTAGs.

According to some of the various aspects of embodiments, TA maintenance,pathloss reference handling and a timing reference for a pTAG may followLTE release 10 principles in the MCG and/or SCG. The UE may need tomeasure downlink pathloss to calculate uplink transmit power. A pathlossreference may be used for uplink power control and/or transmission ofrandom access preamble(s). UE may measure downlink pathloss usingsignals received on a pathloss reference cell. For SCell(s) in a pTAG,the choice of a pathloss reference for cells may be selected from and/orbe limited to the following two options: a) the downlink SCell linked toan uplink SCell using system information block 2 (SIB2), and b) thedownlink pCell. The pathloss reference for SCells in a pTAG may beconfigurable using RRC message(s) as a part of an SCell initialconfiguration and/or reconfiguration. According to some of the variousaspects of embodiments, a PhysicalConfigDedicatedSCell informationelement (IE) of an SCell configuration may include a pathloss referenceSCell (downlink carrier) for an SCell in a pTAG. The downlink SCelllinked to an uplink SCell using system information block 2 (SIB2) may bereferred to as the SIB2 linked downlink of the SCell. Different TAGs mayoperate in different bands. For an uplink carrier in an sTAG, thepathloss reference may be only configurable to the downlink SCell linkedto an uplink SCell using the system information block 2 (SIB2) of theSCell.

To obtain initial uplink (UL) time alignment for an sTAG, an eNB mayinitiate an RA procedure. In an sTAG, a UE may use one of any activatedSCells from this sTAG as a timing reference cell. In an exampleembodiment, the timing reference for SCells in an sTAG may be the SIB2linked downlink of the SCell on which the preamble for the latest RAprocedure was sent. There may be one timing reference and one-timealignment timer (TAT) per TA group. A TAT for TAGs may be configuredwith different values. In a MAC entity, when a TAT associated with apTAG expires: all TATs may be considered as expired, the UE may flushHARQ buffers of serving cells, the UE may clear any configured downlinkassignment/uplink grants, and the RRC in the UE may release PUCCH/SRSfor all configured serving cells. When the pTAG TAT is not running, ansTAG TAT may not be running. When the TAT associated with an sTAGexpires: a) SRS transmissions may be stopped on the correspondingSCells, b) SRS RRC configuration may be released, c) CSI reportingconfiguration for corresponding SCells may be maintained, and/or d) theMAC in the UE may flush the uplink HARQ buffers of the correspondingSCells.

An eNB may initiate an RA procedure via a PDCCH order for an activatedSCell. This PDCCH order may be sent on a scheduling cell of this SCell.When cross carrier scheduling is configured for a cell, the schedulingcell may be different than the cell that is employed for preambletransmission, and the PDCCH order may include an SCell index. At least anon-contention based RA procedure may be supported for SCell(s) assignedto sTAG(s).

FIG. 9 is an example message flow in a random access process in asecondary TAG as per an aspect of an embodiment of the presentinvention. An eNB transmits an activation command 600 to activate anSCell. A preamble 602 (Msg1) may be sent by a UE in response to a PDCCHorder 601 on an SCell belonging to an sTAG. In an example embodiment,preamble transmission for SCells may be controlled by the network usingPDCCH format 1A. Msg2 message 603 (RAR: random access response) inresponse to the preamble transmission on the SCell may be addressed toRA-RNTI in a PCell common search space (CSS). Uplink packets 604 may betransmitted on the SCell in which the preamble was transmitted.

According to some of the various aspects of embodiments, initial timingalignment may be achieved through a random access procedure. This mayinvolve a UE transmitting a random access preamble and an eNB respondingwith an initial TA command NTA (amount of timing advance) within arandom access response window. The start of the random access preamblemay be aligned with the start of a corresponding uplink subframe at theUE assuming NTA=0. The eNB may estimate the uplink timing from therandom access preamble transmitted by the UE. The TA command may bederived by the eNB based on the estimation of the difference between thedesired UL timing and the actual UL timing. The UE may determine theinitial uplink transmission timing relative to the correspondingdownlink of the sTAG on which the preamble is transmitted.

The mapping of a serving cell to a TAG may be configured by a servingeNB with RRC signaling. The mechanism for TAG configuration andreconfiguration may be based on RRC signaling. According to some of thevarious aspects of embodiments, when an eNB performs an SCell additionconfiguration, the related TAG configuration may be configured for theSCell. In an example embodiment, an eNB may modify the TAG configurationof an SCell by removing (releasing) the SCell and adding(configuring) anew SCell (with the same physical cell ID and frequency) with an updatedTAG ID. The new SCell with the updated TAG ID may initially be inactivesubsequent to being assigned the updated TAG ID. The eNB may activatethe updated new SCell and start scheduling packets on the activatedSCell. In an example implementation, it may not be possible to changethe TAG associated with an SCell, but rather, the SCell may need to beremoved and a new SCell may need to be added with another TAG. Forexample, if there is a need to move an SCell from an sTAG to a pTAG, atleast one RRC message, for example, at least one RRC reconfigurationmessage, may be send to the UE to reconfigure TAG configurations byreleasing the SCell and then configuring the SCell as a part of the pTAG(when an SCell is added/configured without a TAG index, the SCell may beexplicitly assigned to the pTAG). The PCell may not change its TA groupand may always be a member of the pTAG.

The purpose of an RRC connection reconfiguration procedure may be tomodify an RRC connection, (e.g. to establish, modify and/or release RBs,to perform handover, to setup, modify, and/or release measurements, toadd, modify, and/or release SCells). If the received RRC ConnectionReconfiguration message includes the sCellToReleaseList, the UE mayperform an SCell release. If the received RRC Connection Reconfigurationmessage includes the sCellToAddModList, the UE may perform SCelladditions or modification.

In LTE Release-10 and Release-11 CA, a PUCCH is only transmitted on thePCell (PSCell) to an eNB. In LTE-Release 12 and earlier, a UE maytransmit PUCCH information on one cell (PCell or PSCell) to a given eNB.

As the number of CA capable UEs and also the number of aggregatedcarriers increase, the number of PUCCHs and also the PUCCH payload sizemay increase. Accommodating the PUCCH transmissions on the PCell maylead to a high PUCCH load on the PCell. A PUCCH on an SCell may beintroduced to offload the PUCCH resource from the PCell. More than onePUCCH may be configured for example, a PUCCH on a PCell and anotherPUCCH on an SCell. FIG. 10 is an example grouping of cells into PUCCHgroups as per an aspect of an embodiment of the present invention. Inthe example embodiments, one, two or more cells may be configured withPUCCH resources for transmitting CSI/ACK/NACK to a base station. Cellsmay be grouped into multiple PUCCH groups, and one or more cell within agroup may be configured with a PUCCH. In an example configuration, oneSCell may belong to one PUCCH group. SCells with a configured PUCCHtransmitted to a base station may be called a PUCCH SCell, and a cellgroup with a common PUCCH resource transmitted to the same base stationmay be called a PUCCH group.

In Release-12, a PUCCH can be configured on a PCell and/or a PSCell, butcannot be configured on other SCells. In an example embodiment, a UE maytransmit a message indicating that the UE supports PUCCH configurationon a PCell and SCell. Such an indication may be separate from anindication of dual connectivity support by the UE. In an exampleembodiment, a UE may support both DC and PUCCH groups. In an exampleembodiment, either DC or PUCCH groups may be configured, but not both.In another example embodiment, more complicated configurationscomprising both DC and PUCCH groups may be supported.

When a UE is capable of configuring PUCCH groups, and if a UE indicatesthat it supports simultaneous PUCCH/PUSCH transmission capability, itmay imply that the UE supports simultaneous PUCCH/PUSCH transmission onboth PCell and SCell. When multiple PUCCH groups are configured, a PUCCHmay be configured or not configured with simultaneous PUCCH/PUSCHtransmission.

In an example embodiment, PUCCH transmission to a base station on twoserving cells may be realized as shown in FIG. 10 . A first group ofcells may employ a PUCCH on the PCell and may be called PUCCH group 1 ora primary PUCCH group. A second group of cells may employ a PUCCH on anSCell and may be called PUCCH group 2 or a secondary PUCCH group. One,two or more PUCCH groups may be configured. In an example, cells may begrouped into two PUCCH groups, and each PUCCH group may include a cellwith PUCCH resources. A PCell may provide PUCCH resources for theprimary PUCCH group and an SCell in the secondary PUCCH group mayprovide PUCCH resources for the cells in the secondary PUCCH group. Inan example embodiment, no cross-carrier scheduling between cells indifferent PUCCH groups may be configured. When cross-carrier schedulingbetween cells in different PUCCH groups is not configured, ACK/NACK onPHICH channel may be limited within a PUCCH group. Both downlink anduplink scheduling activity may be separate between cells belonging todifferent PUCCH groups.

A PUCCH on an SCell may carry HARQ-ACK and CSI information. A PCell maybe configured with PUCCH resources. In an example embodiment, RRCparameters for an SCell PUCCH Power Control for a PUCCH on an SCell maybe different from those of a PCell PUCCH. A Transmit Power Controlcommand for a PUCCH on an SCell may be transmitted in DCI(s) on theSCell carrying the PUCCH.

UE procedures on a PUCCH transmission may be different and/orindependent between PUCCH groups. For example, determination of DLHARQ-ACK timing, PUCCH resource determination for HARQ-ACK and/or CSI,Higher-layer configuration of simultaneous HARQ-ACK+CSI on a PUCCH,Higher-layer configuration of simultaneous HARQ-ACK+SRS in one subframemay be configured differently for a PUCCH PCell and a PUCCH SCell.

A PUCCH group may be a group of serving cells configured by a RRC anduse the same serving cell in the group for transmission of a PUCCH. APrimary PUCCH group may be a PUCCH group containing a PCell. A secondaryPUCCH group may be a PUCCH cell group not containing the PCell. In anexample embodiment, an SCell may belong to one PUCCH group. When oneSCell belongs to a PUCCH group, ACK/NACK or CSI for that SCell may betransmitted over the PUCCH in that PUCCH group (over PUCCH SCell orPUCCH PCell). A PUCCH on an SCell may reduce the PUCCH load on thePCell. A PUCCH SCell may be employed for UCI transmission of SCells inthe corresponding PUCCH group.

In an example embodiment, a flexible PUCCH configuration in whichcontrol signalling is sent on one, two or more PUCCHs may be possible.Beside the PCell, it may be possible to configure a selected number ofSCells for PUCCH transmission (herein called PUCCH SCells). Controlsignalling information conveyed in a certain PUCCH SCell may be relatedto a set of SCells in a corresponding PUCCH group that are configured bythe network via RRC signalling.

PUCCH control signalling carried by a PUCCH channel may be distributedbetween a PCell and SCells for off-loading or robustness purposes. Byenabling a PUCCH in an SCell, it may be possible to distribute theoverall CSI reports for a given UE between a PCell and a selected numberof SCells (e.g. PUCCH SCells), thereby limiting PUCCH CSI resourceconsumption by a given UE on a certain cell. It may be possible to mapCSI reports for a certain SCell to a selected PUCCH SCell. An SCell maybe assigned a certain periodicity and time-offset for transmission ofcontrol information. Periodic CSI for a serving cell may be mapped on aPUCCH (on the PCell or on a PUCCH-SCell) via RRC signalling. Thepossibility of distributing CSI reports, HARQ feedbacks, and/orScheduling Requests across PUCCH SCells may provide flexibility andcapacity improvements. HARQ feedback for a serving cell may be mapped ona PUCCH (on the PCell or on a PUCCH SCell) via RRC signalling.

In example embodiments, PUCCH transmission may be configured on a PCell,as well as one SCell in CA. An SCell PUCCH may be realized using theconcept of PUCCH groups, where aggregated cells are grouped into two ormore PUCCH groups. One cell from a PUCCH group may be configured tocarry a PUCCH. More than 5 carriers may be configured. In the exampleembodiments, up to n carriers may be aggregated. For example, n may be16, 32, or 64. Some CCs may have non-backward compatible configurationssupporting only advanced UEs (e.g. support licensed assisted accessSCells). In an example embodiment, one SCell PUCCH (e.g. two PUCCHgroups) may be supported. In another example embodiment, a PUCCH groupconcept with multiple (more than one) SCells carrying PUCCH may beemployed (e.g., there can be more than two PUCCH groups).

In an example embodiment, a given PUCCH group may not comprise servingcells of both MCG and SCG. One of the PUCCHs may be configured on thePCell. In an example embodiment, PUCCH mapping of serving cells may beconfigured by RRC messages. In an example embodiment, a maximum value ofan SCellIndex and a ServCellIndex may be 31 (ranging from 0 to 31). Inan example, a maximum value of stag-Id may be 3. The CIF for a scheduledcell may be configured explicitly. A PUCCH SCell may be configured bygiving a PUCCH configuration for an SCell. A HARQ feedback and CSIreport of a PUCCH SCell may be sent on the PUCCH of that PUCCH SCell.The HARQ feedback and CSI report of a SCell may sent on a PUCCH of aPCell if no PUCCH SCell is signalled for that SCell. The HARQ feedbackand CSI report of an SCell may be sent on the PUCCH of one PUCCH SCell;hence they may not be sent on the PUCCH of different PUCCH SCell. The UEmay report a Type 2 PH for serving cells configured with a PUCCH. In anexample embodiment, a MAC activation/deactivation may be supported for aPUCCH SCell. An eNB may manage the activation/deactivation status forSCells. A newly added PUCCH SCell may be initially deactivated.

In an example embodiment, independent configuration of PUCCH groups andTAGs may be supported. FIG. 11 and FIG. 12 show example configurationsof TAGs and PUCCH groups. For example, one TAG may contain multipleserving cells with a PUCCH. For example, each TAG may only comprisecells of one PUCCH group. For example, a TAG may comprise the servingcells (without a PUCCH) which belong to different PUCCH groups.

There may not be a one-to-one mapping between TAGs and PUCCH groups. Forexample, in a configuration, a PUCCH SCell may belong to primary TAG. Inan example implementation, the serving cells of one PUCCH group may bein different TAGs and serving cells of one TAG may be in different PUCCHgroups. Configuration of PUCCH groups and TAGs may be left to eNBimplementation. In another example implementation, restriction(s) on theconfiguration of a PUCCH cell may be specified. For example, in anexample embodiment, cells in a given PUCCH group may belong to the sameTAG. In an example, an sTAG may only comprise cells of one PUCCH group.In an example, one-to-one mapping between TAGs and PUCCH groups may beimplemented. In implementation, cell configurations may be limited tosome of the examples. In other implementations, some or all the belowconfigurations may be allowed.

In an example embodiment, for an SCell in a pTAG, the timing referencemay be a PCell. For an SCell in an sTAG, the timing reference may be anyactivated SCell in the sTAG. For an SCell (configured with PUCCH or not)in a pTAG, a pathloss reference may be configured to be a PCell or anSIB-2 linked SCell. For an SCell in a sTAG, the pathloss reference maybe the SIB-2 linked SCell. When a TAT associated with a pTAG is expired,the TAT associated with sTAGs may be considered as expired. When a TATof an sTAG containing PUCCH SCell expires, the MAC may indicate to anRRC to release PUCCH resource for the PUCCH group. When the TAT of ansTAG containing a PUCCH SCell is not running, the uplink transmission(PUSCH) for SCells in the secondary PUCCH group not belonging to thesTAG including the PUCCH SCell may not be impacted. The TAT expiry of ansTAG containing a PUCCH SCell may not trigger TAT expiry of other TAGsto which other SCells in the same PUCCH group belong. When the TATassociated with sTAG not containing a PUCCH SCell is not running, thewireless device may stop the uplink transmission for the SCell in thesTAG and may not impact other TAGs.

In an example embodiment, a MAC entity may have a configurable timertimeAlignmentTimer per TAG. The timeAlignmentTimer may be used tocontrol how long the MAC entity considers the Serving Cells belonging tothe associated TAG to be uplink time aligned. The MAC entity may, when aTiming Advance Command MAC control element is received, apply the TimingAdvance Command for the indicated TAG; start or restart thetimeAlignmentTimer associated with the indicated TAG. The MAC entitymay, when a Timing Advance Command is received in a Random AccessResponse message for a serving cell belonging to a TAG and/or if theRandom Access Preamble was not selected by the MAC entity, apply theTiming Advance Command for this TAG and start or restart thetimeAlignmentTimer associated with this TAG. Otherwise, if thetimeAlignmentTimer associated with this TAG is not running, the TimingAdvance Command for this TAG may be applied and the timeAlignmentTimerassociated with this TAG started. When the contention resolution isconsidered not successful, a timeAlignmentTimer associated with this TAGmay be stopped. Otherwise, the MAC entity may ignore the received TimingAdvance Command.

Example embodiments of the invention may enable operation of multiplePUCCH groups. Other example embodiments may comprise a non-transitorytangible computer readable media comprising instructions executable byone or more processors to cause operation of PUCCH groups. Yet otherexample embodiments may comprise an article of manufacture thatcomprises a non-transitory tangible computer readable machine-accessiblemedium having instructions encoded thereon for enabling programmablehardware to cause a device (e.g. wireless communicator, UE, basestation, etc.) to enable operation of PUCCH groups. The device mayinclude processors, memory, interfaces, and/or the like. Other exampleembodiments may comprise communication networks comprising devices suchas base stations, wireless devices (or user equipment: UE), servers,switches, antennas, and/or the like. In an example embodiment one ormore TAGs may be configured along with PUCCH group configuration.

FIG. 13 is an example MAC PDU as per an aspect of an embodiment of thepresent invention. In an example embodiment, a MAC PDU may comprise of aMAC header, zero or more MAC Service Data Units (MAC SDU), zero or moreMAC control elements, and optionally padding. The MAC header and the MACSDUs may be of variable sizes. A MAC PDU header may comprise one or moreMAC PDU subheaders. A subheader may correspond to either a MAC SDU, aMAC control element or padding. A MAC PDU subheader may comprise headerfields R, F2, E, LCID, F, and/or L. The last subheader in the MAC PDUand subheaders for fixed sized MAC control elements may comprise thefour header fields R, F2, E, and/or LCID. A MAC PDU subheadercorresponding to padding may comprise the four header fields R, F2, E,and/or LCID.

In an example embodiment, LCID or Logical Channel ID field may identifythe logical channel instance of the corresponding MAC SDU or the type ofthe corresponding MAC control element or padding. There may be one LCIDfield for a MAC SDU, MAC control element or padding included in the MACPDU. In addition to that, one or two additional LCID fields may beincluded in the MAC PDU when single-byte or two-byte padding is requiredbut cannot be achieved by padding at the end of the MAC PDU. The LCIDfield size may be, e.g. 5 bits. L or the Length field may indicate thelength of the corresponding MAC SDU or variable-sized MAC controlelement in bytes. There may be one L field per MAC PDU subheader exceptfor the last subheader and subheaders corresponding to fixed-sized MACcontrol elements. The size of the L field may be indicated by the Ffield and F2 field. The F or the Format field may indicate the size ofthe Length field. There may be one F field per MAC PDU subheader exceptfor the last subheader and subheaders corresponding to fixed-sized MACcontrol elements and expect for when F2 is set to 1. The size of the Ffield may be 1 bit. In an example, if the F field is included, and/or ifthe size of the MAC SDU or variable-sized MAC control element is lessthan 128 bytes, the value of the F field is set to 0, otherwise it isset to 1. The F2 or the Format2 field may indicate the size of theLength field. There may be one F2 field per MAC PDU subheader. The sizeof the F2 field may be 1 bit. In an example, if the size of the MAC SDUor variable-sized MAC control element is larger than 32767 bytes and ifthe corresponding subheader is not the last subheader, the value of theF2 field may be set to 1, otherwise it is set to 0. The E or theExtension field may be a flag indicating if more fields are present inthe MAC header or not. The E field may be set to “1” to indicate anotherset of at least R/F2/E/LCID fields. The E field may be set to “0” toindicate that either a MAC SDU, a MAC control element or padding startsat the next byte. R or reserved bit, set to “0”.

MAC PDU subheaders may have the same order as the corresponding MACSDUs, MAC control elements and padding. MAC control elements may beplaced before any MAC SDU. Padding may occur at the end of the MAC PDU,except when single-byte or two-byte padding is required. Padding mayhave any value and the MAC entity may ignore it. When padding isperformed at the end of the MAC PDU, zero or more padding bytes may beallowed. When single-byte or two-byte padding is required, one or twoMAC PDU subheaders corresponding to padding may be placed at thebeginning of the MAC PDU before any other MAC PDU subheader. In anexample, a maximum of one MAC PDU may be transmitted per TB per MACentity, a maximum of one MCH MAC PDU can be transmitted per TTI.

At least one RRC message may provide configuration parameters for atleast one cell and configuration parameters for PUCCH groups. Theinformation elements in one or more RRC messages may provide mappingbetween configured cells and PUCCH SCells. Cells may be grouped into aplurality of cell groups and a cell may be assigned to one of theconfigured PUCCH groups. There may be a one-to-one relationship betweenPUCCH groups and cells with configured PUCCH resources. At least one RRCmessage may provide mapping between an SCell and a PUCCH group, andPUCCH configuration on PUCCH SCell.

System information (common parameters) for an SCell may be carried in aRadioResourceConfigCommonSCell in a dedicated RRC message. Some of thePUCCH related information may be included in common information of anSCell (e.g. in the RadioResourceConfigCommonSCell). Dedicatedconfiguration parameters of SCell and PUCCH resources may be configuredby dedicated RRC signaling using, for example,RadioResourceConfigDedicatedSCell.

The IE PUCCH-ConfigCommon and IE PUCCH-ConfigDedicated may be used tospecify the common and the UE specific PUCCH configuration respectively.

In an example, PUCCH-ConfigCommon may include: deltaPUCCH-Shift:ENUMERATED {ds1, ds2, ds3}; nRB-CQI: INTEGER (0 . . . 98); nCS-AN:INTEGER (0 . . . 7); and/or n1PUCCH-AN: INTEGER (0 . . . 2047). Theparameter deltaPUCCH-Shift (Δ_(shift) ^(PUCCH)), nRB-CQI (N_(RB) ⁽²⁾),nCS-An (N_(cs) ⁽¹⁾), and n1PUCCH-AN (N_(PUCCH) ⁽¹⁾) may be physicallayer parameters of PUCCH.

PUCCH-ConfigDedicated may be employed. PUCCH-ConfigDedicated mayinclude: ackNackRepetition CHOICE{release: NULL, setup: SEQUENCE{repetitionFactor: ENUMERATED {n2, n4, n6, spare1}, n1PUCCH-AN-Rep:INTEGER (0 . . . 2047)}}, tdd-AckNackFeedbackMode: ENUMERATED {bundling,multiplexing}OPTIONAL}. ackNackRepetitionj parameter indicates whetherACK/NACK repetition is configured. n2 corresponds to repetition factor2, n4 to 4 for repetitionFactor parameter (N_(ANRep)). n1PUCCH-AN-Repparameter may be n_(PUCCH,ANRep) ^((1,p)) for antenna port P0 and forantenna port P1. dd-AckNackFeedbackMode parameter may indicate one ofthe TDD ACK/NACK feedback modes used. The value bundling may correspondto use of ACK/NACK bundling whereas, the value multiplexing maycorrespond to ACK/NACK multiplexing. The same value may apply to bothACK/NACK feedback modes on PUCCH as well as on PUSCH.

The parameter PUCCH-ConfigDedicated may include simultaneous PUCCH-PUSCHparameter indicating whether simultaneous PUCCH and PUSCH transmissionsis configured. An E-UTRAN may configure this field for the PCell whenthe nonContiguousUL-RA-WithinCC-Info is set to supported in the band onwhich PCell is configured. The E-UTRAN may configure this field for thePSCell when the nonContiguousUL-RA-WithinCC-Info is set to supported inthe band on which PSCell is configured. The E-UTRAN may configure thisfield for the PUCCH SCell when the nonContiguousUL-RA-WithinCC-Info isset to supported in the band on which PUCCH SCell is configured.

A UE may transmit radio capabilities to an eNB to indicate whether UEsupport the configuration of PUCCH groups. The simultaneous PUCCH-PUSCHin the UE capability message may be applied to both a PCell and anSCell. Simultaneous PUCCH+PUSCH may be configured separately (usingseparate IEs) for a PCell and a PUCCH SCell. For example, a PCell and aPUCCH SCell may have different or the same configurations related tosimultaneous PUCCH+PUSCH.

The eNB may select the PUCCH SCell among current SCells or candidateSCells considering cell loading, carrier quality (e.g. using measurementreports), carrier configuration, and/or other parameters. From afunctionality perspective, a PUCCH Cell group management procedure mayinclude a PUCCH Cell group addition, a PUCCH cell group release, a PUCCHcell group change and/or a PUCCH cell group reconfiguration. The PUCCHcell group addition procedure may be used to add a secondary PUCCH cellgroup (e.g., to add PUCCH SCell and one or more SCells in the secondaryPUCCH cell group). In an example embodiment, cells may be released andadded employing one or more RRC messages. In another example embodiment,cells may be released employing a first RRC message and then addedemploying a second RRC messages.

SCells including PUCCH SCell may be in a deactivated state when they areconfigured. A PUCCH SCell may be activated after an RRC configurationprocedure by an activation MAC CE. An eNB may transmit a MAC CEactivation command to a UE. The UE may activate an SCell in response toreceiving the MAC CE activation command.

In example embodiments, a timer is running once it is started, until itis stopped or until it expires; otherwise it may not be running A timercan be started if it is not running or restarted if it is running. Forexample, a timer may be started or restarted from its initial value.

The scheduling request (SR) is used for requesting UL-SCH resources fornew transmission(s). In DC, scheduling request (SR) may be directlytransmitted from UE to an SeNB via a PSCell. This may reduce schedulingdelay and related signaling load.

When PUCCH groups are configured, SR resources may be configured onPCell, PUCCH SCell, or both. The possibility to have SR resources inPUCCH SCell(s) may allow better distribution of SR load among theserving cells. In an example configuration, an SR for a UE may betransmitted on a serving cell, e.g. either on the PCell or on a givenPUCCH SCell. In some scenarios, there may be more capacity available onthe SCell, and this may be a reason to allocate more SR resources on anPUCCH SCell. If PUCCH on an SCell carries SR signals, the chance of a UEinitiated RA on the PCell due to a scheduling request may be reduced andsignalling overhead and RACH resource usage may be reduced.

In an example implementation, SR resources may be configured on PUCCHSCell and no SR resources may be configured on PCell. In an exampleimplementation, an SR load may be shared among a PUCCH SCell and aPCell. SR resources may be configured on both PCell and PUCCH SCell.Whether to configure SR resources on PCell, on the PUCCH SCell, or onboth PCell and the PUCCH SCell may be up to eNB and/or UEimplementation. SR resources may be configured on both PCell and PUCCHSCell. An SR_COUNTER may be increased when SR is sent on either PUCCHSCell or PCell and sr-ProhibitTimer may be implemented to control thetiming of SR transmission. An SR process may employ SR resources on botha PCell and a PUCCH SCell, when both resources are configured.

In an example implementation, SR resources may be interleaved in timedomain, for example, some subframes (TTIs) may include a valid SRresource on PCell, and some other subframes may include a valid SRresource on the PUCCH SCell. In an example, as shown in FIG. 15 , someTTIs may include a valid SR resource on the PCell, some TTIs may includea valid SR resource on the PUCCH SCell. In an example implementation,some TTIs may include a valid SR resource on both PCell and PUCCH SCell.When SR is configured on both an activated PUCCH SCell and a PCell, theMAC entity uses whichever SR resources comes first. When SR istriggered, it may be transmitted on the first valid SR resourceavailable, regardless of whether SR resources is on PCell or SCell. WhenSR is on PUCCH SCell, there may be gain in terms of load balancing byallowing transmission of SR on an SCell. There may be some latency gainsince there may be more SR resources available on the SCell. The UE maychoose the first SR resources available for transmission of an SR. In anexample, a valid SR resource on PCell and PUCCH SCell may overlap intime. A TTI may not include any valid SR resource or include more thanone valid SR resources (on both PCell and PUCCH SCell). An eNB mayemploy different IEs for configuration of SR resources on PCell andPUCCH SCell. Example embodiments may be applicable to various SRconfiguration implementations on PCell and PUCCH SCell.

In an example embodiment, SR resources may be configured by one or moreinformation elements in an RRC message. For example,SchedulingRequestConfig IE may be employed for configuration of PUCCHresources on the PCell and/or on a PUCCH SCell. TheSchedulingRequestConfig IE may be used to specify some of the schedulingrequest related parameters. The SchedulingRequestConfig IE may beincluded in a dedicated physical layer configuration IE of a UEconfiguration.

The SchedulingRequestConfig IE may comprise an information element toset up or release scheduling resources and other parameters.SchedulingRequestConfig IE may comprise PUCCH resource Index(sr-ConfigIndex), SR configuration index (sr-ConfigIndex), and SRmaximum transmission (dsr-TransMax) IEs. At least one RRC message mayinclude a first SchedulingRequestConfig IE for configuration of SRresources on PCell, and a second SchedulingRequestConfig IE forconfiguration of SR resources on PUCCH SCell. sr-ConfigIndex may beconfigured and sr-PUCCH-ResourceIndex (e.g. sr-PUCCH-ResourceIndex,sr-PUCCH-ResourceIndexP1) may be configured. sr-PUCCH-ResourceIndex,sr-PUCCH-ResourceIndexP1 may be n_(PUCCH,SRI) ^((1,p)) for antenna portP0 and for antenna port P1 respectively. E-UTRAN may configuresr-PUCCH-ResourceIndexP1 if sr-PUCCHResourceIndex is configured.

At least one RRC message configuring SR configuration may also includesr-ProhibitTimer IE to be employed to determine a timer value forscheduling request processes.

When an SR is triggered, the corresponding SR process may be consideredas pending until it is cancelled. Pending SR(s) may be cancelled andsr-ProhibitTimer may be stopped when a MAC PDU is assembled and this PDUincludes a BSR (Buffer Status Report) which contains buffer status up to(and including) the last event that triggered a BSR, or when the ULgrant(s) can accommodate pending data available for transmission. If anSR is triggered and there is no other SR pending, the MAC entity may setthe SR_COUNTER to 0.

As long as one SR is pending, the MAC entity and if no UL-SCH resourcesare available for a transmission in this TTI, and if the MAC entity hasno valid PUCCH resource for SR configured in any TTI: UE (e.g. MACentity) may initiate a Random Access procedure on the SpCell and cancelpending SRs. In an example embodiment, if SR resources are configured ona PUCCH SCell and the PUCCH SCell is deactivated, the MAC entity may nothave a valid PUCCH resource for transmitting an SR signal on adeactivated PUCCH SCell. If SR resources is not configured on a PUCCHSCell, the MAC entity may not have a valid PUCCH resource for SR on thePUCCH SCell.

In an example embodiment, a UE may receive at least one RRC messagecomprising configuration parameters of one or more cells, the RRCmessage may comprise configuration parameters of scheduling requestresources and processes. At least one RRC message may comprise a firstSR maximum transmission information element (IE) for the PCell and asecond SR maximum transmission information element for the PUCCH SCell.The at least one message may comprise a common SR prohibit timerinformation element which is used for both PCell and PUCCH SCell.

The at least one message may comprise a first scheduling requestconfiguration index for scheduling request resources on the primaryPUCCH, if SR resources on PCell is configured. The first schedulingrequest configuration index may indicate a first scheduling requestperiod and a first offset as shown in example FIG. 14 . The at least onemessage may further comprise a second scheduling request configurationindex for scheduling request resources on the secondary PUCCH, if SRresources are configured for a PUCCH SCell. The second schedulingrequest configuration index may indicate a second scheduling requestperiod and a second offset as shown in example FIG. 14 .

In an example embodiment, an RRC message may comprise configurationparameters of SR resources on both a PCell and an SCell. In anotherexample embodiment, a first RRC message may configuration parameters ofSR resources on the PCell and a second RRC message may configurationparameters of SR resources on an SCell. The at least one RRC message maycomprise the first RRC message and the second RRC message.

At least one RRC message configuring SR configuration may also includesr-ProhibitTimer information element comprising a timer value forscheduling request processes. The value of IE sr-ProhibitTimer may be innumber of SR period(s). Value 0 means no timer for SR transmission onPUCCH is configured. Value 1 corresponds to one SR period, Value 2corresponds to 2*SR periods and so on.

At least one RRC message configuring SR configuration may also includedsr-TransMax IE in SchedulingRequestConfig IE. In an example embodiment,dsr-TransMax may take the value of n4, n8, n16, n32, or n64. The valuen4 corresponds to 4 transmissions, n8 corresponds to 8 transmissions andso on.

A UE may be configured by higher layers to transmit the SR on oneantenna port or two antenna ports of the serving cell with configuredPUCCH. The scheduling request may be transmitted on the PUCCHresource(s) n_(PUCCH) ^((1,{tilde over (p)}))=n_(PUCCH,SRI)^((1,{tilde over (p)})) for {tilde over (p)} mapped to antenna port p,where n_(PUCCH,SRI) ^((1,{tilde over (p)})) may be configured by higherlayers unless the SR coincides in time with the transmission of HARQ-ACKusing PUCCH Format 3 in which case the SR may be multiplexed withHARQ-ACK. The SR configuration for SR transmission periodicitySR_(PERIODICITY) and SR subframe offset N_(OFFSET,SR) may be defined,for example, as shown in FIG. 14 by the parameter sr-ConfigIndex I_(SR)given by higher layers. SR transmission instances in a serving cellconfigured with SR are the uplink subframes satisfying(10×n_(f)+└n_(s)/2┘−N_(OFFSET,SR))mod SR_(PERIODICITY)=0.

In an example embodiment, SR resources may be configured by eNB in a waythat TTIs with available SR resources in a PCell and an SCell do notoverlap. The time difference between two subsequent subframes with SRresources may be reduced when SR resources are configured on both PCelland PUCCH SCell.

When an SR is triggered, it may be considered as pending until it iscancelled. Pending SR(s) may be cancelled and sr-ProhibitTimer may bestopped when a MAC PDU is assembled and this PDU includes a BSR (BufferStatus Report) which contains buffer status up to (and including) thelast event that triggered a BSR, or when the UL grant(s) can accommodatepending data available for transmission. If an SR is triggered and thereis no other SR pending, the MAC entity may set the SR_COUNTER to 0.

In an example embodiment, whether to configure scheduling request onlyon PCell, only on the PUCCH SCell, or on both PCell and PUCCH SCell isup to eNB implementation. When SR is configured on both activated PUCCHSCell and PCell, the MAC entity may use whichever SR opportunity comesfirst for SR transmission. Based on the UE implementation, the MACentity may choose one of SRs when SRs are configured on PUCCH SCell(s)and PCell in the same TTI. In a MAC entity, there may be only onescheduling request procedure regardless of whether scheduling request isconfigured on multiple cells, e.g. one SR_COUNTER which is increasedwhen SR is sent on either PCell or PUCCH SCell and one sr-ProhibitTimer.

In a wireless device, as long as one SR is pending, and if no UL-SCHresources are available for a transmission in this TTI, and if the MACentity has no valid PUCCH resource for SR configured in any TTI:initiate a Random Access procedure and cancel pending SRs. In an exampleembodiment, if SR resources are configured on a PUCCH SCell and thePUCCH SCell is deactivated, the MAC entity may not have a valid PUCCHresource for SR on a deactivated PUCCH SCell. If SR is not configured ona PUCCH SCell, the MAC entity may not have a valid PUCCH resource for SRon the PUCCH SCell. If SR resources are configured on a PUCCH SCell andthe TAT associated with the TAG of the PUCCH SCell is not running, theMAC entity may not have a valid PUCCH resource for transmitting SR onthe PUCCH SCell. In an example embodiment, a PUCCH SCell has valid SRresources in a subframe, if SR is configured for the SCell in thesubframe, the PUCCH SCell is activated in the subframe, and the TATassociated with the TAG of PUCCH SCell is running in the subframe. IfTAT of a PUCCH SCell is expired, then PUCCH resources of the SCell isreleased and the PUCCH SCell is no longer considered an SCell withconfigured PUCCH and SR resources. SR resources may be configured for anSCell that is in a TAG that its TAT is not running. In such a case, theSCell does not have valid SR resources until the TAG is uplinksynchronized. When SR resources are not configured for a serving cell,that serving cell does not have valid SR resources.

Various example scenarios when an SCell has valid or invalid SRresources are illustrated in FIGS. 16, 17, 18, and 19 .

FIG. 16 shows example events and states corresponding to a secondarycell as per an aspect of an embodiment of the present invention. When anSCell with configured PUCCH resources is deactivated, the SCell does notinclude valid SR resources. For example, subframe A does not have validSR resources. In an example embodiment, a PUCCH SCell has valid SRresources in a subframe, if SR is configured for the SCell in thesubframe, the PUCCH SCell is activated in the subframe, and the TATassociated with the TAG of PUCCH SCell is running in the subframe. Forexample, subframe B is configured with SR resources and include valid SRresources.

FIG. 17 shows example events and states corresponding to a secondarycell as per an aspect of an embodiment of the present invention. When anSCell with configured PUCCH resources is deactivated, the SCell does notinclude valid SR resources. For example, subframe C does not have validSR resources. When an SCell with configured PUCCH resources is activatedbut is in a TAG that its TAT is not running, the SCell does not includevalid SR resources. For example, subframe D does not have valid SRresources. In an example embodiment, a PUCCH SCell has valid SRresources in a subframe, if SR is configured for the SCell in thesubframe, the PUCCH SCell is activated in the subframe, and the TATassociated with the TAG of PUCCH SCell is running in the subframe. Forexample, subframe E is configured with SR resources and include valid SRresources.

In an example embodiment, a wireless device may receive at least onemessage comprising: i) first configuration parameters of a primary cellin a plurality of cells. The plurality of cells are grouped into aplurality of timing advance groups (TAGs) comprising a primary TAG and asecondary TAG. ii) second configuration parameters of a secondary cell,the secondary cell having configured second SR resources in a firstplurality of subframes. The wireless device may receive a MAC activationcommand for activation of the secondary cell in the secondary TAG. Thesecondary TAG may have a timing alignment timer (TAT) that is notrunning. The wireless device may determine that the secondary cell hasinvalid SR resource in a subframe in the first plurality of subframeswhen: an SR is pending in the subframe; the TAT is not running in thesubframe; and the second SR resources are configured in the subframe andthe wireless device does not have any uplink data channel resources areavailable for transmission in the subframe.

In an example embodiment, a wireless device may receive at least onemessage comprising: i) first configuration parameters of a primary cellin a plurality of cells. The plurality of cells are grouped into aplurality of timing advance groups (TAGs) comprising a secondary TAG.ii) second configuration parameters of a secondary cell. The secondarycell has a configured second SR resources in a first plurality ofsubframes. The wireless device may receive a MAC activation command foractivation of the secondary cell in the secondary TAG. The secondary TAGmay have a timing alignment timer (TAT) that is not running. Thewireless device may determine that the secondary cell has invalid SRresource in a subframe in the first plurality of subframes when: an SRis pending in the subframe; the TAT is not running in the subframe; andthe second SR resources are configured in the subframe.

In an example embodiment, a UE may receive at least one RRC messagecomprising configuration parameters of scheduling request resources andprocesses. At least one RRC message may comprise a first SchedulingRequest Configuration IE for PCell and a second Scheduling RequestConfiguration IE for an SCell. Scheduling Request Configuration IE(s)may comprise parameters (IEs) such as sr-PUCCH-ResourceIndex,sr-ConfigIndex, dsr-TransMax, and/or sr-PUCCH-ResourceIndexP1. The atleast one RRC message may also comprise a MAC-Main configuration IEcomprising a SR prohibit timer information element.

In an example embodiment, if the MAC entity has at least one valid PUCCHresource for SR configured for this TTI and if this TTI is not part of ameasurement gap and if sr-ProhibitTimer is not running:→IfSR_COUNTER<dsr-TransMax, then UE may perform one or more of thefollowing: UE may increment SR_COUNTER by 1; UE may instruct thephysical layer to signal SR on one valid SR resource; and/or UE maystart the sr-ProhibitTimer; Else UE may perform one, more than one, orall the following (this may be considered an SR failure): UE may notifyRRC to release PUCCH/SRS for one or more first serving cells; UE mayclear configured downlink assignments and uplink grants; and/or UE mayinitiate a Random Access procedure (e.g. on the PCell) and cancelpending SRs

In an example embodiment, in a MAC entity, there may be only onescheduling request procedure regardless of whether scheduling request isconfigured on multiple cells, e.g., one SR_COUNTER which is increasedwhen SR is sent on either PCell or PUCCH SCell and one sr-ProhibitTimer.

In an example embodiment, a UE may transmit an SR signal on a validPUCCH resource for SR. A UE may initiate a Random Access procedure (e.g.on the PCell) and cancel all pending SRs, if the UE has no valid SRresource for SR configured in any TTI. A valid SR resource may beavailable for SR on a PCell or SPCell, when SR is configured on thecell. A valid SR resource may be available for SR on an SCell if SRresources are configured on the SCell, and if the SCell is activated andif TAT of the TAG associated with PUCCH SCell is running SR signaltransmissions may not be allowed on a deactivated SCell. The SR resourceon a deactivated SCell may be considered as an invalid SR resource. TheSR resource on an SCell of a TAG that its TAT is not running may not beconsidered as a valid SR resource. The SR configuration, on SCell of aTAG when its TAT is expired, may be released. When SR configuration on acell is released, SR resource is not available on the cell. In anexample embodiment, valid SR resources for SR may include the SRresources configured on PCell that belong to a TAG that its TAT isrunning Valid SR resources for SR may include the SR resourcesconfigured on an activated PUCCH SCell that belong to a TAG that its TATis running.

In an example embodiment, SR resources may be configured on an SCell butnot on the PCell. If SR is triggered and PUCCH SCell is deactivated,Random Access may be triggered (e.g. on the PCell). SR resources on anSCell may not be released upon PUCCH SCell deactivation by a UE. In anexample embodiment, SR resources may be configured on an SCell but noton the PCell. If SR is triggered and PUCCH SCell is activated in a TAGthat its TAT is not running, Random Access may be triggered (e.g. on thePCell).

In an example embodiment, a wireless device may receive at least one RRCmessage comprising: i) first configuration parameters of a primary cellin a plurality of cells. The plurality of cells are grouped into aplurality of timing advance groups (TAGs) comprising a primary and asecondary TAG. The primary cell may have no scheduling request (SR)resources. ii) second configuration parameters of a secondary cell. Thesecondary cell may have configured second SR resources in a firstplurality of subframes. The wireless device may receive a MAC activationcommand for activation of the secondary cell in the secondary TAG. Thesecondary TAG may have a timing alignment timer (TAT) that is notrunning. The wireless device may initiate a random access procedurewhen: an SR is pending in a subframe in the first plurality ofsubframes; the TAT is not running in the subframe; and no uplink datachannel resources are available for transmission in the subframe. Thesecond SR resources may be configured in the subframe.

In an example embodiment, a wireless device may receive at least onefirst RRC message comprising first configuration parameters of a primarycell in a plurality of cells. The plurality of cells being grouped intoa plurality of timing advance groups (TAGs) comprising a secondary TAG.The primary cell has no scheduling request (SR) resources. The wirelessdevice may receive at least one second message comprising secondconfiguration parameters of a secondary cell in the secondary TAG. Thesecondary cell has configured second SR resources and is in activatedstate. The secondary TAG has a timing alignment timer (TAT) that is notrunning. The wireless device may initiate a random access procedurewhen: the secondary cell is activated; an SR is pending in a subframe;the TAT is not running in the subframe; and no uplink data channelresources are available for transmission in the subframe.

Various example scenarios when an SCell has valid or invalid SRresources are illustrated in FIGS. 16, 17, 18, and 19 .

FIG. 18 shows example events and states corresponding to a secondarycell as per an aspect of an embodiment of the present invention. When anSCell with configured PUCCH/SR resources is activated and uplinksynchronized (corresponding TAT is running), the SCell includes valid SRresources. For example, subframe F may include valid SR resources. In anexample embodiment, when the TAT of a TAG including the SCell expires,the UE/eNG may release PUCCH and SR resources on the SCell. The SCellmay not have any valid SR resources. For example, subframe G may nothave valid SR resources. The eNB may transmit one or more RRC messagesto configure the SCell with PUCCH/resources. The SCell may then beactivated and have configured PUCCH/SR resources. The TAT of the TAGincluding the SCell may not be running, and the SCell may not includeany valid SR resources. For example, subframe H may not have any validSR resources. The eNB may initiate a random access process on the TAG.The PUCCH SCell has valid SR resources in a subframe, if SR isconfigured for the SCell in the subframe, the PUCCH SCell is activatedin the subframe, and the TAT associated with the TAG of PUCCH SCell isrunning in the subframe. For example, subframe I is configured with SRresources and include valid SR resources.

FIG. 19 shows example events and states corresponding to a secondarycell as per an aspect of an embodiment of the present invention. ThePUCCH SCell has valid SR resources in a subframe, if SR is configuredfor the SCell in the subframe, the PUCCH SCell is activated in thesubframe, and the TAT associated with the TAG of PUCCH SCell is runningin the subframe. For example, subframe J is configured with SR resourcesand include valid SR resources. A deactivated PUCCH SCell may notinclude a valid SR resources. For example, subframe J1 may not includeany valid SR resources.

FIG. 20 shows example events and states corresponding to a secondarycell as per an aspect of an embodiment of the present invention. TheSCell with configured SR resources may belong to a TAG that its TAT isuplink synchronized. The PUCCH SCell has valid SR resources in asubframe, if SR is configured for the SCell in the subframe, the PUCCHSCell is activated in the subframe, and the TAT associated with the TAGof PUCCH SCell is running in the subframe. For example, subframe K isconfigured with SR resources and include valid SR resources. When TAT ofthe TAG expires, PUCCH of the SCell may be released and the SCell maynot have valid SR resources. A PUCCH SCell that is not uplinksynchronized (is out of sync) may not include a valid SR resources. Forexample, subframe L may not include any valid SR resources.

In example FIGS. 16, 17, 18, and 19 show various example events andstates corresponding to a secondary cell as per an aspect of anembodiment of the present invention. In an example, in subframe A inFIG. 16 , a wireless device may initiate a random access process when anSR is pending in subframe A and no uplink shared channel resources areavailable in subframe A. The same applies to subframes C, D, G, and H inFIG. 17 and FIG. 18 . The wireless device may transmit an SR requestwhen the PUCCH SCell has valid SR resources, for example, in subframe B,E, F, and I, when these subframes are configured with SR resources onthe PUCCH SCell.

In an example embodiment, consider a scenario when SR resources are notconfigured on PCell and is configured on PUCCH SCell. The wirelessdevice may transmit an SR on a valid SR resource of an SCell in a firstsubframe as a part of an SR process. In an example, in a second subframeafter the first subframe, the PUCCH SCell may be deactivated for examplebecause the wireless device received a MAC activation/deactivationcommand deactivating the PUCCH SCell. In another example, in a secondsubframe after the first subframe, a TAT of a timing advance groupassociated with the PUCCH SCell may expire. The wireless device maycancel the SR and initiate a random access process, if the SR process ispending in the second subframe and no uplink data channel resources areavailable for transmission in the second subframe. In an exampleembodiment, the wireless device may not wait for SR prohibit timer toexpire before initiating the random access procedure. In an exampleembodiment, the wireless device may not wait for an uplink grant inresponse to the SR and may initiate the random access procedure.

For example, SR prohibit timer may be 80 msec. The wireless device maytransmit an SR in subframe n. In subframe n+2, the wireless device maycancel SR process and initiate a random access process if the PUCCHSCell is deactivated and/or the TAT of the TAG associated with PUCCHSCell is expired. This process may reduce the delay for receiving anuplink grant.

In example FIG. 19 and FIG. 20 , the wireless device may transmit an SRin subframes J and K. In FIG. 19 , if an SR process is pending and SCellis deactivated and no uplink shared channel was not available to thewireless device, then the wireless device may initiate a random accessprocess. In FIG. 20 , if SR is pending and the TAT of the TAG associatedwith PUCCH SCell is expired and no uplink shared channel was notavailable to the wireless device, then the wireless device may initiatea random access process.

An eNB may or may not have received the SR request. The wireless devicemay not count on the eNB to the pending SR and may initiate the randomaccess process. In some example scenarios, the eNB may receive both SRand the random access preamble.

In an example embodiment, a wireless device may receive at least onemessage comprising: a) first configuration parameters of a primary cellin a plurality of cells. The primary cell has no scheduling request (SR)resources. b) second configuration parameters of a secondary cell. Thesecondary cell has configured second SR resources. The wireless devicemay transmit an SR associated with an SR process in the second SRresources in a first subframe. The wireless device may monitor at leastone downlink control channel for a grant for uplink data channelresources. The wireless device may cancel the SR process and initiate arandom access procedure when: the SR process is pending; a TAT of atiming advance group associated with the secondary cell expires (the TATis not running); and no uplink data channel resources are available fortransmission.

In an example embodiment, a wireless device may receive at least one atleast one message comprising: a) first configuration parameters of aprimary cell in a plurality of cells. The primary cell has no schedulingrequest (SR) resources. b) second configuration parameters of asecondary cell. The secondary cell has configured second SR resources.The wireless device may transmit an SR associated with an SR process inthe second SR resources in a first subframe. The wireless device maymonitor at least one downlink control channel for a grant for uplinkdata channel resources. The wireless device may cancel the SR processand initiate a random access procedure when: the SR process is pending;said secondary cell is deactivated; no uplink data channel resources areavailable for transmission.

The random access procedures may be initiated by the UE on the PCell andmay be a contention based random access procedure. SR resources mayremain configured on the SCell during the random access procedures untiland after the random access process is successful and UE is granteduplink resources. If a TAT of the sTAG including the SCell is notrunning, the eNB may trigger a random access process to uplinksynchronize the secondary TAG. When the secondary TAG is uplinksynchronized (its TAT is running), then UE may be able to employ the SRresources of the SCell to transmit SR request.

An eNB may configure SR of a UE on PCell or PUCCH SCell or bothdepending on many factors, e.g. the resource availability, reliability,and/or other implementation-related inputs.

In an example embodiment, MAC entity may consider that it has validPUCCH resource in a subframe for SR in SCell, if PUCCH resource isconfigured in SCell in the subframe; and if the SCell is activated inthe subframe and if TAT of the TAG associated with the SCell is runningin the subframe. MAC entity considers it has valid PUCCH resource for SRin PCell/SPCell, if PUCCH resource is configured in PCell/SPCell(PCell/SPCell is always activated when configured).

MAC entity may not consider that it has valid PUCCH resource for SR inan SCell, if PUCCH resource is not configured in the SCell. In asubframe, MAC entity may not consider that it has valid PUCCH resourcefor SR in an SCell, if PUCCH resource is configured in the SCell in thesubframe and the SCell is deactivated in the subframe. In a subframe,MAC entity may not consider that it has valid PUCCH resource for SR inan SCell, if PUCCH resource is configured in the SCell in the subframeand TAT of the TAG associated with the SCell is running in the subframe.A PUCCH SCell may be configured and then activated in a TAG that is notyet synchronized or is out-of-sync (its TAT is expired). In suchscenarios, TAT of the TAG associated with PUCCH SCell is not running,while PUCCH resources and SR resources are configured. The UE (e.g. MACentity) may not consider that the PUCCH SCell has a valid SR resourceson the PUCCH SCell.

FIG. 21 is an example flow diagram as per an aspect of an embodiment ofthe present invention. A wireless device may receive at least onemessage from a base station at 2110. The wireless device may compriseone or more processors and memory storing instructions that, whenexecuted, cause the wireless device to perform a method. The message(s)may comprise configuration parameters of a plurality of cells. Accordingto an embodiment, the plurality of cells may be grouped into a pluralityof physical uplink control channel (PUCCH) groups. The PUCCH groups maycomprise a primary PUCCH group comprising the primary cell with aprimary PUCCH transmitted to a base station. The PUCCH groups maycomprise a secondary PUCCH group comprising the secondary cell with asecondary PUCCH transmitted to the base station. According to anembodiment, the configuration parameters may comprise: firstconfiguration parameters of a primary PUCCH for the primary cell; andsecond configuration parameters of a secondary PUCCH for the secondarycell. The plurality of cells may comprise a primary cell and a secondarycell. The primary cell may have no configured scheduling request (SR)resources. The secondary cell may have configured SR resources. Thesecondary cell may be in a secondary timing advance group (sTAG).According to an embodiment, the SR resources may be configured on thesecondary cell in the subframe.

According to an embodiment, the plurality of cells may be grouped into aplurality of timing advance groups (TAGs). The TAGs may comprise aprimary TAG and an sTAG. The primary TAG may comprise the primary cell.The sTAG may comprise the secondary cell. According to an embodiment,the at least one message may comprise a time alignment timer parameterfor the sTAG and a time alignment timer for the pTAG.

An activation command indicating activation of the secondary cell may bereceived by the wireless device from the base station at 2120. Thesecondary cell may be in an activated state in the subframe. Accordingto an embodiment, the method may further comprise initiating the SRprocess when the wireless device has one or more uplink packets fortransmission.

A random access procedure may be initiated at 2130. The random accessprocedure may be initiated when in the subframe an SR process ispending; no uplink data channel resources are available fortransmission; and a time alignment timer of the sTAG is not runningAccording to an embodiment, the method may further comprise transmittinga random access preamble in random access resources of the primary cell.According to an embodiment, the method may further comprise receiving arandom access response comprising an uplink grant.

FIG. 22 is an example flow diagram as per an aspect of an embodiment ofthe present invention. A wireless device may receive at least onemessage at 2210. The wireless device may comprise one or more processorsand memory storing instructions that, when executed, cause the wirelessdevice to perform a method. The at least one message may compriseconfiguration parameters of a secondary cell configured with schedulingrequest (SR) resources. The secondary cell may be in a secondary timingadvance group (sTAG).

According to an embodiment, the at least one message may compriseconfiguration parameters of a plurality of cells. The plurality of cellsmay be grouped into a plurality of physical uplink control channel(PUCCH) groups. The PUCCH groups may comprise a primary PUCCH group anda secondary PUCCH group. The primary PUCCH group may comprise a primarycell with a primary PUCCH transmitted to a base station. The secondaryPUCCH group may comprise the secondary cell with a secondary PUCCHtransmitted to the base station. According to an embodiment, the atleast one message may comprise first configuration parameters of aprimary PUCCH for a primary cell, and second configuration parameters ofa secondary PUCCH for the secondary cell.

An activation command may be received at 2220. The activation commandmay indicate activation of the secondary cell. According to anembodiment, the secondary cell may be in an activated state in thesubframe. According to an embodiment, the at least one message maycomprise second configuration parameters of a plurality of cells. Theplurality of cells may be grouped into a plurality of timing advancegroups (TAGs). The plurality of TAGs may comprise: a primary TAGcomprising a primary cell; and the sTAG comprising the secondary cell.According to an embodiment, the at least one message may comprise a timealignment timer parameter for the sTAG and a time alignment timer forthe pTAG. According to an embodiment, the method may further compriseinitiating the SR process when the wireless device has one or moreuplink packets for transmission.

At 2230, the secondary cell may be determined to have an invalid SRresource when first conditions are met. For example, at 2230, thesecondary cell may be determined to have an invalid SR resource when ina subframe: an SR process is pending; the SR resources are configured inthe subframe; and a time alignment timer of the sTAG is not running inthe subframe. According to an embodiment, the SR resources may beconfigured on the secondary cell in the subframe. According to anembodiment, no uplink data channel resources may be available fortransmission in the subframe. According to an embodiment, the method mayfurther comprise initiating a random access process on the primary cellwhen no uplink data channel resources are available for transmission inthe subframe.

FIG. 23 is an example flow diagram as per an aspect of an embodiment ofthe present invention. A wireless device may receive at least onemessage at 2310. The wireless device may comprise one or more processorsand memory storing instructions that, when executed, cause the wirelessdevice to perform a method. The at least one message may compriseconfiguration parameters of a plurality of cells. The plurality of cellsmay comprise: a primary cell with no configured scheduling request (SR)resources; and a secondary cell with configured SR resources. Thesecondary cell may be in a secondary timing advance group (sTAG).According to an embodiment, the secondary cell may be in an activatedstate in the subframe.

According to an embodiment, the plurality of cells may be grouped into aplurality of physical uplink control channel (PUCCH) groups. The PUCCHgroups may comprise a primary PUCCH group and a secondary PUCCH group.The primary PUCCH group may comprise the primary cell with a primaryPUCCH transmitted to a base station. The secondary PUCCH group maycomprise the secondary cell with a secondary PUCCH transmitted to thebase station. According to an embodiment, the at least one message maycomprise: first configuration parameters of a primary PUCCH for theprimary cell; and second configuration parameters of a secondary PUCCHfor the secondary cell.

According to an embodiment, the method may further comprise the wirelessdevice initiating the SR process when the wireless device has one ormore uplink packets for transmission. At 2320, an SR associated with anSR process may be transmitted in the SR resources. An SR prohibit timermay not be running.

At 2330, at least one downlink control channel may be monitored foruplink grants. At 2340, a random access procedure may be initiated andthe SR process cancelled when in a subframe: the SR process is pending;no uplink data channel resources are available for transmission; and atime alignment timer of the sTAG is not running According to anembodiment, the plurality of cells may be grouped into a plurality oftiming advance groups (TAGs). The TAGs may comprise a primary TAG andthe sTAG. The primary TAG may comprise the primary cell. The sTAG maycomprise the secondary cell. According to an embodiment, the at leastone message may comprise a time alignment timer parameter for the sTAGand a time alignment timer for the pTAG. According to an embodiment, themethod may further comprise transmitting a random access preamble inrandom access resources of the primary cell. According to an embodiment,the method may further comprise receiving a random access responsecomprising an uplink grant.

The configured set of serving cells for a UE may, according to someembodiments, comprise of one PCell and one or more SCells.

According to an embodiment, an IE PhysicalConfigDedicated element may beemployed to specify UE specific physical channel configuration(s).According to an embodiment: PhysicalConfigDedicated may compriseSEQUENCE {schedulingRequestConfig SchedulingRequestConfig OPTIONAL,—Need ON [ . . . ]}. According to an embodiment:PhysicalConfigDedicatedSCell may comprise SEQUENCE{schedulingRequestConfig SchedulingRequestConfig OPTIONAL, —Need ON [ .. . ]}.

According to an embodiment, a Timing Advance Group may comprise a groupof serving cells that may be configured by RRC and that, for the cellswith an UL configured, use the same timing reference cell and the sameTiming Advance value. A Primary Timing Advance Group may comprise aTiming Advance Group comprising the PCell. A Secondary Timing AdvanceGroup may comprise a Timing Advance Group not containing the PCell.

According to an embodiment, the Activation/Deactivation MAC controlelement may be identified by a MAC PDU subheader with an LCID. TheScheduling Request (SR) may be employed for requesting UL-SCH resourcesfor new transmission. When an SR is triggered, it may be considered aspending until it is cancelled. Pending SR(s) may be cancelled andsr-ProhibitTimer may be stopped when a MAC PDU is assembled and this PDUcomprises a BSR which contains buffer status up to (and including) thelast event that triggered a BSR. Pending SR(s) may be cancelled andsr-ProhibitTimer may be stopped if pending SR(s) are triggered bySidelink BSR, when a MAC PDU is assembled and this PDU comprises aSidelink BSR which comprises buffer status up to (and including) thelast event that triggered a Sidelink BSR. Pending SR(s) may be cancelledand sr-ProhibitTimer may be stopped if pending SR(s) are triggered bySidelink BSR, when upper layers configure autonomous resource selection.Pending SR(s) may be cancelled and sr-ProhibitTimer may be stopped whenthe UL grant(s) may accommodate pending data available for transmission.

According to an embodiment, if an SR is triggered and there is no otherSR pending, the MAC entity may set an SR_COUNTER to 0. According to anembodiment, as long as one SR is pending, the MAC entity may for eachTTI, if no UL-SCH resources are available for a transmission in thisTTI, if the MAC entity has no valid PUCCH resource for SR configured inany TTI: initiate a Random Access procedure on the SpCell and cancelpending SRs. Else if the MAC entity has at least one valid PUCCHresource for SR configured for this TTI and if this TTI is not part of ameasurement gap and if sr-ProhibitTimer is not running: ifSR_COUNTER<dsr-TransMax: increment SR_COUNTER by 1; instruct thephysical layer to signal the SR on one valid PUCCH resource for SR; andstart the sr-ProhibitTimer. Else: notify RRC to release PUCCH forserving cells; notify RRC to release SRS for serving cells; clear anyconfigured downlink assignments and uplink grants; and initiate a RandomAccess procedure on the SpCell and cancel pending SRs. The selection ofwhich valid PUCCH resource for SR to signal SR on when the MAC entityhas more than one valid PUCCH resource for SR in one TTI may be left toa UE implementation.

In this specification, “a” and “an” and similar phrases are to beinterpreted as “at least one” and “one or more.” In this specification,the term “may” is to be interpreted as “may, for example.” In otherwords, the term “may” is indicative that the phrase following the term“may” is an example of one of a multitude of suitable possibilities thatmay, or may not, be employed to one or more of the various embodiments.If A and B are sets and every element of A is also an element of B, A iscalled a subset of B. In this specification, only non-empty sets andsubsets are considered. For example, possible subsets of B={cell1,cell2} are: {cell1}, {cell2}, and {cell1, cell2}.

In this specification, parameters (Information elements: IEs) maycomprise one or more objects, and each of those objects may comprise oneor more other objects. For example, if parameter (IE) N comprisesparameter (IE) M, and parameter (IE) M comprises parameter (IE) K, andparameter (IE) K comprises parameter (information element) J, then, forexample, N comprises K, and N comprises J. In an example embodiment,when one or more messages comprise a plurality of parameters, it impliesthat a parameter in the plurality of parameters is in at least one ofthe one or more messages, but does not have to be in each of the one ormore messages.

Many of the elements described in the disclosed embodiments may beimplemented as modules. A module is defined here as an isolatableelement that performs a defined function and has a defined interface toother elements. The modules described in this disclosure may beimplemented in hardware, software in combination with hardware,firmware, wetware (i.e. hardware with a biological element) or acombination thereof, all of which are behaviorally equivalent. Forexample, modules may be implemented as a software routine written in acomputer language configured to be executed by a hardware machine (suchas C, C++, Fortran, Java, Basic, Matlab or the like) or amodeling/simulation program such as Simulink, Stateflow, GNU Octave, orLabVIEWMathScript. Additionally, it may be possible to implement modulesusing physical hardware that incorporates discrete or programmableanalog, digital and/or quantum hardware. Examples of programmablehardware comprise: computers, microcontrollers, microprocessors,application-specific integrated circuits (ASICs); field programmablegate arrays (FPGAs); and complex programmable logic devices (CPLDs).Computers, microcontrollers and microprocessors are programmed usinglanguages such as assembly, C, C++ or the like. FPGAs, ASICs and CPLDsare often programmed using hardware description languages (HDL) such asVHSIC hardware description language (VHDL) or Verilog that configureconnections between internal hardware modules with lesser functionalityon a programmable device. Finally, it needs to be emphasized that theabove mentioned technologies are often used in combination to achievethe result of a functional module.

The disclosure of this patent document incorporates material which issubject to copyright protection. The copyright owner has no objection tothe facsimile reproduction by anyone of the patent document or thepatent disclosure, as it appears in the Patent and Trademark Officepatent file or records, for the limited purposes required by law, butotherwise reserves all copyright rights whatsoever.

While various embodiments have been described above, it should beunderstood that they have been presented by way of example, and notlimitation. It will be apparent to persons skilled in the relevantart(s) that various changes in form and detail can be made thereinwithout departing from the spirit and scope. In fact, after reading theabove description, it will be apparent to one skilled in the relevantart(s) how to implement alternative embodiments. Thus, the presentembodiments should not be limited by any of the above describedexemplary embodiments. In particular, it should be noted that, forexample purposes, the above explanation has focused on the example(s)using FDD communication systems. However, one skilled in the art willrecognize that embodiments of the invention may also be implemented in asystem comprising one or more TDD cells (e.g. frame structure 2 and/orframe structure 3-licensed assisted access). The disclosed methods andsystems may be implemented in wireless or wireline systems. The featuresof various embodiments presented in this invention may be combined. Oneor many features (method or system) of one embodiment may be implementedin other embodiments. Only a limited number of example combinations areshown to indicate to one skilled in the art the possibility of featuresthat may be combined in various embodiments to create enhancedtransmission and reception systems and methods.

In addition, it should be understood that any figures which highlightthe functionality and advantages, are presented for example purposesonly. The disclosed architecture is sufficiently flexible andconfigurable, such that it may be utilized in ways other than thatshown. For example, the actions listed in any flowchart may bere-ordered or only optionally used in some embodiments.

Further, the purpose of the Abstract of the Disclosure is to enable theU.S. Patent and Trademark Office and the public generally, andespecially the scientists, engineers and practitioners in the art whoare not familiar with patent or legal terms or phraseology, to determinequickly from a cursory inspection the nature and essence of thetechnical disclosure of the application. The Abstract of the Disclosureis not intended to be limiting as to the scope in any way.

Finally, it is the applicant's intent that only claims that include theexpress language “means for” or “step for” be interpreted under 35U.S.C. 112, paragraph 6. Claims that do not expressly include the phrase“means for” or “step for” are not to be interpreted under 35 U.S.C. 112.

The invention claimed is:
 1. A method comprising: receiving, by awireless device, an indication of: a primary cell that is not configuredwith scheduling request (SR) resources; and a secondary cell that isconfigured with SR resources and that is in a secondary cell group; andinitiating a random access procedure based on: an SR process, associatedwith the SR resources, being pending in a time interval; the wirelessdevice not having an uplink data channel resource available in the timeinterval; and the wireless device not having a valid timing advance forthe secondary cell in the time interval.
 2. The method of claim 1,wherein the initiating the random access procedure comprises sending arandom access preamble.
 3. The method of claim 1, further comprisingreceiving a random access response comprising an uplink grant.
 4. Themethod of claim 1, further comprising determining to cancel the SRprocess.
 5. The method of claim 1, wherein the time interval comprisesat least one of: a frame, a subframe, a transmission time interval(TTI), a slot, or a symbol.
 6. The method of claim 1, furthercomprising: determining to perform the SR process based on the wirelessdevice having one or more uplink packets for transmission.
 7. The methodof claim 1, wherein the receiving the indication comprises receivingconfiguration parameters of a plurality of cells comprising the primarycell and the secondary cell.
 8. The method of claim 7, wherein theconfiguration parameters comprise: first configuration parameters of aprimary physical uplink control channel (PUCCH) for the primary cell;and second configuration parameters of a secondary PUCCH for thesecondary cell.
 9. The method of claim 7, wherein the plurality of cellsare grouped into a plurality of physical uplink control channel (PUCCH)groups comprising: a primary PUCCH group comprising the primary cell,wherein the primary cell is configured for a transmission of a primaryPUCCH signal to a base station; and a secondary PUCCH group comprisingthe secondary cell, wherein the secondary cell is configured for atransmission of a secondary PUCCH signal to the base station.
 10. Themethod of claim 7, wherein the plurality of cells are grouped into aplurality of timing advance groups (TAGs) comprising: a primary TAGcomprising the primary cell; and a secondary TAG comprising thesecondary cell.
 11. A wireless device comprising: one or moreprocessors; and memory storing instructions that, when executed by theone or more processors, cause the wireless device to: receive anindication of: a primary cell that is not configured with schedulingrequest (SR) resources; and a secondary cell that is configured with SRresources and that is in a secondary cell group; and initiate a randomaccess procedure based on: an SR process, associated with the SRresources, being pending in a time interval; the wireless device nothaving an uplink data channel resource available in the time interval;and the wireless device not having a valid timing advance for thesecondary cell in the time interval.
 12. The wireless device of claim11, wherein the instructions, when executed by the one or moreprocessors, cause the wireless device to initiate the random accessprocedure by sending a random access preamble.
 13. The wireless deviceof claim 11, wherein the instructions, when executed by the one or moreprocessors, further cause the wireless device to receive a random accessresponse comprising an uplink grant.
 14. The wireless device of claim11, wherein the instructions, when executed by the one or moreprocessors, further cause the wireless device to determine to cancel theSR process.
 15. The wireless device of claim 11, wherein the timeinterval comprises at least one of: a frame, a subframe, a transmissiontime interval (TTI), a slot, or a symbol.
 16. The wireless device ofclaim 11, wherein the instructions, when executed by the one or moreprocessors, cause the wireless device to determine to perform the SRprocess based on the wireless device having one or more uplink packetsfor transmission.
 17. The wireless device of claim 11, wherein theinstructions, when executed by the one or more processors, cause thewireless device to receive the indication by causing: receivingconfiguration parameters of a plurality of cells comprising the primarycell and the secondary cell.
 18. The wireless device of claim 17,wherein the configuration parameters comprise: first configurationparameters of a primary physical uplink control channel (PUCCH) for theprimary cell; and second configuration parameters of a secondary PUCCHfor the secondary cell.
 19. The wireless device of claim 17, wherein theplurality of cells are grouped into a plurality of physical uplinkcontrol channel (PUCCH) groups comprising: a primary PUCCH groupcomprising the primary cell, wherein the primary cell is configured fora transmission of a primary PUCCH signal to a base station; and asecondary PUCCH group comprising the secondary cell, wherein thesecondary cell is configured for a transmission of a secondary PUCCHsignal to the base station.
 20. The wireless device of claim 17, whereinthe plurality of cells are grouped into a plurality of timing advancegroups (TAGs) comprising: a primary TAG comprising the primary cell; anda secondary TAG comprising the secondary cell.
 21. A method comprising:sending, by a base station and to a wireless device, an indication of: aprimary cell that is not configured with scheduling request (SR)resources; and a secondary cell that is configured with SR resources andthat is in a secondary cell group; and receiving a random accesspreamble of a random access procedure that is initiated based on: an SRprocess, associated with the SR resources, being pending in a timeinterval; the wireless device not having an uplink data channel resourceavailable in the time interval; and the wireless device not having avalid timing advance for the secondary cell in the time interval. 22.The method of claim 21, wherein the secondary cell is in an activatedstate in the time interval.
 23. The method of claim 21, furthercomprising sending a random access response comprising an uplink grant.24. The method of claim 21, wherein the time interval comprises at leastone of: a frame, a subframe, a transmission time interval (TTI), a slot,or a symbol.
 25. The method of claim 21, wherein the sending theindication comprises sending configuration parameters of a plurality ofcells comprising the primary cell and the secondary cell.
 26. The methodof claim 25, wherein the configuration parameters comprise: firstconfiguration parameters of a primary physical uplink control channel(PUCCH) for the primary cell; and second configuration parameters of asecondary PUCCH for the secondary cell.
 27. The method of claim 25,wherein the plurality of cells are grouped into a plurality of physicaluplink control channel (PUCCH) groups comprising: a primary PUCCH groupcomprising the primary cell, wherein the primary cell is configured fora transmission of a primary PUCCH signal to a base station; and asecondary PUCCH group comprising the secondary cell, wherein thesecondary cell is configured for a transmission of a secondary PUCCHsignal to the base station.
 28. The method of claim 25, wherein theplurality of cells are grouped into a plurality of timing advance groups(TAGs) comprising: a primary TAG comprising the primary cell; and asecondary TAG (sTAG) comprising the secondary cell.
 29. The method ofclaim 28, wherein the configuration parameters comprise a time alignmenttimer parameter for the sTAG.
 30. A base station comprising: one or moreprocessors; and memory storing instructions that, when executed by theone or more processors, cause the base station to: send, to a wirelessdevice, an indication of: a primary cell that is not configured withscheduling request (SR) resources; and a secondary cell that isconfigured with SR resources and that is in a secondary cell group; andreceive a random access preamble of a random access procedure that isinitiated based on: an SR process, associated with the SR resources,being pending in a time interval; the wireless device not having anuplink data channel resource available in the time interval; and thewireless device not having a valid timing advance for the secondary cellin the time interval.
 31. The base station of claim 30, wherein thesecondary cell is in an activated state in the time interval.
 32. Thebase station of claim 30, wherein the instructions, when executed by theone or more processors, cause the base station to send a random accessresponse comprising an uplink grant.
 33. The base station of claim 30,wherein the time interval comprises at least one of: a frame, asubframe, a transmission time interval (TTI), a slot, or a symbol. 34.The base station of claim 30, wherein the instructions, when executed bythe one or more processors, cause the base station to send theindication by causing: sending configuration parameters of a pluralityof cells comprising the primary cell and the secondary cell.
 35. Thebase station of claim 34, wherein the configuration parameters comprise:first configuration parameters of a primary physical uplink controlchannel (PUCCH) for the primary cell; and second configurationparameters of a secondary PUCCH for the secondary cell.
 36. The basestation of claim 34, wherein the plurality of cells are grouped into aplurality of physical uplink control channel (PUCCH) groups comprising:a primary PUCCH group comprising the primary cell, wherein the primarycell is configured for a transmission of a primary PUCCH signal to abase station; and a secondary PUCCH group comprising the secondary cell,wherein the secondary cell is configured for a transmission of asecondary PUCCH signal to the base station.
 37. The base station ofclaim 34, wherein the plurality of cells are grouped into a plurality oftiming advance groups (TAGs) comprising: a primary TAG comprising theprimary cell; and a secondary TAG (sTAG) comprising the secondary cell.38. The base station of claim 37, wherein the configuration parameterscomprise a time alignment timer parameter for the sTAG.